If you qualify as a transportation industry worker, you can use the DOT per diem rate of $63 ($68 outside the continental United States) from January 1, 2017 through December 31, 2017. The rates were updated to $63 ($68 outside the continental United States) starting October 1, 2015.
The IRS allows you to deduct 80% of your unreimbursed DOT per diem, but you only need to figure your unreimbursed per diem for the year – TurboTax will calculate the rest.
Click here for Instructions on how to claim per diem in TurboTax.